May 12, 2010

It was built in 1930, very much for the same reason as the Church of the Good Shepherd at Tekapo to honour the pioneers of its district, particularly the Burnett family.

As with the Tekapo church, in a thousand years when archaeologists and pilgrims go in search of ancient relics, St. David’s will still be there. It has the lasting qualities of the Celtic and Saxon churches of Britain. Its design, not surprisingly, won for Herbert Hall the New Zealand Institute of Architects Gold Medal for 1934.

This Church was built to the glory of God as a memorial to the pioneers of the Mackenzie Country. Congregations of the three main Churches worship regularly in the Church, which offers awe inspiring views of the lake and mountains through the altar window.

The foundation stone was laid by HRH the Duke of Gloucester, on January 15, 1935.

The builders of the Church were instructed that the site was to be left undisturbed, and that even the matagouri bushes surrounding the building were to remain. Rocks which happened to be on the wall lines were not to be removed. The stones for the wall were to be procured within a radius of five miles of the site, and were to be unchipped and in their natural condition.

April 09, 2010

April 07, 2010

Lay the paving down, working in an area of about 1m (3 ft) square at a time. Fit the pieces together like a jigsaw, keeping the gaps small, and then re-arrange them until you are happy with their position. You may find that you need to trim some pieces to size. It is usually best to place the large pieces first, and then use the smaller ones to infill the gaps.

Check that central slabs are level with the edging pieces and bed them on sand or a 5 cm thick bed of mortar (10 parts grit sand to 1 part cement). Use a mallet or a block of wood and a hammer to bed each piece firmly in position. Test each piece to ensure that it doesn't rock or move; lift pieces and remove or add mortar or sand as necessary until they are firm and level.

After finishing our concrete pavers section, we moved onto creating a path to join our pavers to the roadside. We decided to construct this from Schist, we spent two days at the other campus stealing massive slabs of rock.... then shaping them to paver style.

We dug out the old path and compacted the ground in preparation, laid out some dividing boards to allow for movement over time.

The term "crazy paving" refers to the 'crazed' appearance of the finished surface,it is undertaken as an allegedly simple alternative to more traditional paving, or because broken flags are free or cheaper than intact units, yet, from a contractor's point of view, it costs more in terms of labour to lay a given area of crazy paving than it does for 'normal' paving.

Laying stones to get correct positions before mortar

Well-laid Crazy Paving minimises the amount of mortar or jointing visible at the finished surface. The mortar is the structural weak point of the pavement, so, the less of it there is, the better the finshed work's chances of survival beyond the first winter. All too often, Crazy Paving is badly laid, with great dollops of mortar between the pieces of stone and the whole lot fails within a couple of years.

The Goldfields Mining Centre is a well-known visitor attraction on the main road to Queenstown. The site is 25 hectares in size spread-out along the banks of the Kawarau River in its spectacular gorge.

As the main demonstration site for gold mining, Goldfields depicts a wide range of machinery and mining techniques to show how the early miners extracted gold from this rich field. The extraordinary stamper battery linked to the goldmine; the California sluice guns and numerous examples of hand operated tools combine to provide a complete picture of goldmining as it was carried out in Southern New Zealand.

And there is still gold to be found. It is estimated that less than a third of the gold has been taken from the site. While commercial mining is no longer permitted, the Centre is licensed for gold fossicking and many visitors find and take home with them gold they have found in the virgin soils.

March 24, 2010

March 12, 2010

A metamorphic schist from central Otago essentially the same stone as the hyde grey it has been selected from hyde schist for its exellent brown tones. An ideal building stone with good grain and workability.

Alexandra Brown Schist

This richly coloured schist from central otago contains many warm colours of brown with hints of sienna and white quartz. This schist has a typical rustic look and colour found in the south island when laid traditionally. Looks exeptional when machined and laid in a modern contemporary drystack style due to its natural colour and texture.

Cluden Schist

Cluden Schist is from the Cluden Station Valley in the Tarras region also known by some as 'Wanaka schist' and is easily one of the best building stones available. It has a light grey colour base with hints of brown typical of the Tarras region and a perfectly straight grain ideal for dry-stack styles. This stone produces some of the best schist paving slabs.

Gibbston Schist

A Metamorphic Schist from Central Otago near Arrowtown a Queenstown favorite. A uniformly light grey stone with many linear quartz lines with very few occasional light brown tones where the stone has oxidised which can be hand selected out if required. It has an silver/shimmery effect and is the favorite of many New Zealand stonemasons due to its natural grain. When it is split down to a thin profile and laid in a tight dry-stack style it can be very eye catching and contemporary,

Clutha Schist

An Otago Schist from the Tarras region predominenly grey with flecks of brown and black layers, has an overall pastel tone to it. Ideally suited to the oldern smeared mortar join of the gold rush era. The picture shown is a recessed mortar random ashlar bond dry-stack style.

Hyde Grey Schist

A Metamorphic schist from the Hyde region of central Otago, mostly a light grey with suttle softening brown tones here and there. Hyde grey is easily one of the best 'building' schist stones available, not only has it got an attractive colour but also it has a hardness and grain that is ideal for stonemasons. It can be split cleanly along the grain with ease, whilst also being hard enough to enable a clean and accurate 'cross grain' cut with use of an hydraulic guillotine without crushing the stone, this makes it an ideal building stone.

Poolburn Schist

A metamorphic schist from central Otago and the favorite of many stonemasons, has a good natural grain making it ideally suited for beginner DIYers. It Produces a traditional schist look, with warm autumn colours.

Start from the straightest convenient edge, and lay your pavers with a space of 2mm to 4mm between them. Some pavers have spacer nibs which achieve that automatically. The space allows joint sand to penetrate around the pavers. Always lay uphill if possible.

Lay all full pavers first: then cut and lay any pieces. Cut pavers with a diamond concrete saw, paver splitter (both available from hire centres) or, for small areas, a bolster.

Don't run vehicles over the paving until it's completely finished. To get a loaded wheelbarrow across, lay heavy planks down as running boards

Compacting The Pavers:

Your pavers now need to be consistently compacted over the whole area.

For a small area, use a rubber hammer on a short length of heavy timber: saya piece of 150 x 50mm. For most other jobs, hire a vibrating plate compactor.

When the pavers are all compacted, sweep jointing sand over the whole area and compact again. The compactor will drive the sand into the joints. Keep sweeping and compacting until all joints are filled.

Joint sand should be fine dry plaster sand with angular particles that lock well together. It is also sold as paving sand and some types incorporate a weed preventative

In most cases further maintenance will be unnecessary. Where your paving is subject to heavy runoff, washing or vacuuming; you may need to top up the joint sand periodically. Special sealers and jointing sands are available. Ask your placemakers Firth Centre. Should you need to lift your pavers to get at underground services, relay them following the same procedures.

No particles should have a diameter more than one third of the thickness of the required base course layer.

It should contain no soil or plant material.

Lay geotextile fabric first where soft clay which might push into and through the base course material.

For layers of 100mm thick of more, use 40mm all in aggregate.

Preparing The Sub-grade:

Even after excavating, the sub grade might have holes that need filling to bring it up to the desired level. Fill these with base material, and compact in layers no more than 100mm thick using a plate compactor or rammer.

The finished sub-grade level should match within 20mm, the contour of the finished paving

Preparing Base Course:

This should also be laid in layers no thicker than 100mm and compacted to a uniform dense condition, especially around manholes and kerbs. The finished texture of the base course should not allow bedding sand to filter through.

The final surface of the base course should match the contour of your finished paving with no bumps, and no holes deeper than 10mm.

Bedding sand supports your pavers, but will not hide irregularities in the base course. It should be damp but not wet, coarse river sand (not beach sand).

Don't compact bedding sand directly. It compacts under the pavers. To test how much the thickness will reduce, spread some sand over a small area. Laya paver on top, and thump that with a rubber hammer. The resulting reduction in sand thickness will tell you how much your sand compacts.

Pave in manageable sized areas. Spread sand only over an area you know you can finish in one session. Spread the sand to slightly more than the depth your rubber hammer test indicated would produce a compacted sand depth of between 20mm and 30mm. That will usually be 35mm to 40mm.

Screed the sand to a uniform level. As with any screeding, you need guides or runners at each side to run your screed board on. If you have already laid a soldier or kerb course, you may be able to use that to support your runners. If not, you'll need to drive pegs, and fix your runners to them, just like concrete boxing.

The manageable way to lay hardwearing paths, patios, courtyards and driveways, while avoiding the sameness of plain concrete. Pavers can be laid in stages, and even better, lifted if drains, cables or pipes underneath need servicing

Tools

Pencil

Tape Measure

String lines

Spirit level

Spade

Shovel

Rake

Broom

Screed board

Plate compactor {Hired}

Concrete saw/Paver splitter/Bolster

Planning

Draw the area you want to pave, to scale. From that, estimate the quantities you need.

Buying Tips

Buy all your pavers from one outlet and from the same batch if possible. That avoids differences in colour that can result from different batches. If you can't buy all one batch, mix the pavers up before laying.

CriteriaWeight of traffic: some pavers can withstand only pedestrian use. Others will take light vehicle traffic. Even stronger pavers will handle heavy vehicles. Check specifications with PlaceMakers.

Paver shape and sizeShould suit the size and shape of the area being paved.

Laying pattern

Again, this should suit the area being paved. Options include:

45 degree herringbone,

stretcher bond;

basket weave;

soldier courses along the edges.

Extensive areas of paving, particularly when large of soft top soil have to be dug out, require large volumes of materials. There are four main materials:

Pavers

Bedding sand

Base course material (usually)

Jointing sand

Digging Out

Determine the finished level of the highest part of your paving. Against buildings, that should be at least 150mm below the level of concrete floors, or below the ground level under timber floors. From there, your paving should slope between 15mm to 30mm per metre away from the building. That prevents water ponding or running under buildings.

Dig out the area to be paved to the combined depth of the three layers, ie. pavers, bedding sand and base course.

Paver thickness is set by the expected weight of traffic.

Bedding sand is laid between 20mm and 3Omm thick.

Base course is the only variable. It is the foundation of your paving. The thickness of the base course depends on the firmness of the underlying ground, or "sub-grade". Soft sub-grade has to be dug out deeper, because it needs a thicker base course than hard sub-grade. To test the sub-grade, dig down to about 200mm in several places within the planned paved area, then test the hardness of the sub-grade by walking on and stamping your heel into it.

Schistis medium grade metamorphic rock, formed by the metamorphosis of mudstone/ shale, or some types of igneous rock, to a higher degree than slate, i.e. it has been subjected to higher temperatures and pressures.

The resulting foliationis coarser and more distinct than that of slate due to the higher degree of crystallisation of mica minerals (biotite, chlorite, muscovite) forming larger crystals, and is often referred to as schistosity.

These larger crystals reflect light so that schist often has a high lustre, i.e. it is shiny.

Porphyroblastsare common in schist, and they provide information on the temperature and pressure conditions under which the rock formed.

Due to the more extreme formation conditions, schist often shows complex folding patterns. There are many varieties of schist and they are named for the dominant mineral comprising the rock, e.g. mica schist, green schist (green because of high chlorite content), garnetschist etc.

Built across the face of a bank or slope to keep soil from slipping.Are used to retain features such as terraces, cuttings, embankments and the soil of raised beds and planters.Are amongst the oldest and most basic of stone structures.Are often required in the early stages of a construction project, as areas are levelled off.Adequate drainage for a retaining wall must be provided.Retaining walls can be either gravity or cantilever types.

Dry stone tips:

Back of the wall is built overhand or even sometimes from above.

Batter may be steeper with frames replaced with line bars.

Walls built on steep slopes may require different foundation detail.

Wall tops can be either topped formally with stone work or finished with soil/turf.

The Build:

Day 1 And 2:

Dug out the bank, cleared debris and levelled the site as much as possible.

Placed out a string line, placed stakes to create batter.

Laid footings. Long axis going into the wall where rock size would allow.

Checked footings for stability, packed with gravel and small angular stones.

Started building up the wall in horizontal layers, filling in the back with material and keeping sones on a good level base.

Placed some stones running long ways into bank to insure stability.

Continued to fill the cavity behind wall with soil, gravel and old concrete.

Notes:

Had to redo part of my section, as a rock futher down the wall was pulling on the string line. This caused a slight bump in the wall.